“What is now coming out of Brussels is very very ambitious,” Krueger said on Wednesday at an auto industry conference.

The EU’s proposal calls for a 30 percent reduction in the average CO2 emission of carmakers’ fleets by 2030 compared with 2021 levels. It also sets an interim goal of a 15 percent reduction by 2025 to help ensure automakers start investments early.

The current limit of 95 grams of CO2 per kilometer by 2021 cannot be reached without an adequate share of diesel-engine vehicles, Krueger said, adding this will probably also apply to the newly-announced 2025 interim target.